The design of network architectures has become increasingly complex as the chips connected by inter-node networkshave emerged as distributed systems in their own right, complete with their own on-chip networks. In Anton 2, a massively parallel special-purpose supercomputer for molecular dynamics simulations, we managed this complexity by reusing the on-chip network as a switch for inter-node traffic. This unified network approach introduces several design challenges. Maintaining fairness within… CONTINUE READING